Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The experiments were carried out on broiler chickens divided randomly into two groups differing in the feeding level and, consequently, in the rate of weight gain. Half the chickens in each group were given a single dose of glucagon 150 micrograms/kg, and the other half received a control solution of glycine buffer. The chickens were investigated 1--1.5 hour after feeding and after 18--20 hours of starvation using the technique of biopsy of the liver and the external pectoral muscle. In the biopsy specimens the glycogen level was determined immediately before glucagon administration and 30--60--90 minutes after the injection. It was found that glucagon injection caused either a rise or a fall in the glycogen level in the liver and that the trend of these changes depended on the feeding level of the chickens and on the duration of starvation of the birds before treatment. The glycogen level in the pectoral muscle of the chickens kept on the higher feeding level was observed to fall one hour after glucagon administration.
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PMID:Glucagon effect on glycogen content of chicken liver and muscles. 50 56

Hepatic glycogen was assayed in young and adult rats subjected to sialoadenectomy and/or thymectomy and starvation. Sialoadenectomy in young, but not in adult rats caused the rats to stop feeding. In young, but not in adult sialoadenectomized and starved rats the glycogen level was notably higher than in unoperated and starved rats, indicating active participation of salivary glucagon in immature animals in hepatic glycogenolysis under conditions of starvation. Simultaneous sialoadenectomy and thymectomy caused glycogen depletion in the liver of young rats in spite of the absence of the salivary glands. Acceleration of glycogenolysis in these rats was not due to thymectomy, being probably a result of excessive secretion of adrenal catecholamines.
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PMID:The influence of sialoadenectomy, thymectomy and starvation on liver glycogen in the rat. 55 41

Hormonal and substrate profiles and urinary nitrogen and urea excretion were measured in 78 underweight patients admitted for surgical investigation, who were placed into either a normo- or a hyperketonemic group, depending upon their levels of acetoacetate and beta-hydroxybutyrate. The two groups were otherwise similar in terms of weight loss, arm muscle circumference, triceps skinfold thickness, and serum protein levels. Before surgery only one-quarter of them were hyperketonemic displaying mean glucose, insulin, and glucagon levels characteristic of starvation-adaption, and excreted significantly less urinary nitrogen than in normoketonemic group. Those patients who underwent surgery tended to retain their presurgery hormonal and substrate profile. The normoketonemic group excreted significantly greater amounts of urinary nitrogen, depleted body protein to a greater extent as evidenced by larger changes in arm muscle circumference and serum protein levels, and mortality was greater. Interference with insulin-glucagon balance by sepsis and disease is suggested as a possible explanation for the failure of three-quarters of the patients to become starvation-adapted. The implications of this finding on the parenteral feeding of undernourished patients are discussed.
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PMID:Ketosis and nitrogen excretion in undernourished surgical patients. 57 67

The phenomenon of natriuresis during the early phase of total starvation has been described in man and rabbit. We have examined the pattern of electrolyte excretion initiated by starvation for 4 days in the male Wistar rat. Within 24 hr sodium excretion is significantly diminished when compared to prestarvation values (control 2.55 +/- 0.76 [S.D.] mEq/day; 1-day fast 0.42 +/- 0.27) and by day 2 is less than one tenth of the control value. Chloride retention parallels this sodium conservation. Concomitant changes in urinary pH and ammonia excretion (UNH4V) reflect the mild acidosis of starvation (control pH 7.46 +/- 0.18 [S.D.], UNH4V 0.21 +/- 0.08 [S.D.] mEq/day; day 2 pH 6.10 +/- 0.31, UNH4V 0.71 +/- 0.21). However, the excretion of organic acids is not elevated but is actually decreased by day 2 (control 1.02 +/- 0.21 [S.D.] mEq/day; day 2 0.66 +/- 0.26). The majority of the organic acids are excreted as salts (day-2 0.51 +/- 0.21). This level of excretion does not obligate excessive sodium loss and can be adequately matched by renal ammonia production. Normal plasma glucose levels are maintained, consistent with the well-documented increase in renal gluconeogenesis in the starved rat. Plasma levels of glucagon, a known natriuretic and ketogenic agent, do not rise, and this together with a normal plasma glucose concentration may account for the failure of the rat to exhibit the natriuresis of starvation that is observed in man and rabbit.
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PMID:Renal sodium conservation during starvation in the rat. 64 88

Adenylosuccinase activity of rat liver is depressed by prolonged starvation, cortisol administration, high protein diets, and alloxan diabetes. The loss of activity is not due to the accumulation of a dissociable inhibitor or loss of a cofactor. Starvation produces no loss in activity for 1 day; thereafter the activities of the liver and spleen enzyme decay with a half-life of about 0.9 day. Starvation produces no change in the activity of the kidney, brain, and skeletal muscle enzyme. Refeeding restores the activity of the liver enzyme to the fed level, with only a slight overshoot. The recovery of adenylosuccinase activity is equally rapid after refeeding a balanced diet, or corn oil, or glucose, and is not inhibited by injection of glucagon, in contrast to malic enzyme activity. Recovery is inhibited by cycloheximide, indicating the involvement of protein synthesis. Althouth adenylosuccinase is depressed in liver of starving rat it is elevated in liver of starving chicken. Starvation depresses malic enzyme activity and elevates alanine aminotransferase activity in both species. When rats are starved, the rate of de novo synthesis of adenine mononucleotide decreases in spleen and liver but not in kidney, suggesting a regulatory role for adenylosuccinase in purine biosynthesis. The low activity of adenylosuccinase in liver of severely starved rats is inconsistent with the proposal (Moss, K. M., and McGivan, J.D. (1975) Biochem. J. 150, 275-283) that the purine nucleotide cycle plays a major role in ammonia production for urea synthesis, at least under these conditions.
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PMID:Effect of diet on adenylosuccinase activity in various organs of rat and chicken. 69 Jan 30

Fatty acid synthesis in the mammary gland of lactating rats in vivo was 5-fold higher than in the liver. Starvation decreased fatty acid synthesis in the gland 50-fold, whereas refeeding for 2h completely reversed this change. The plasma insulin concentration decreased 2-fold in starvation and was restored to the fed-rat value on refeeding. Glucagon and prolactin concentrations did not always change in parallel with lipogenesis, suggesting that insulin may be a regulator of this process in the gland.
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PMID:Evidence for a role of insulin in the regulation of lipogenesis in lactating rat mammary gland. Measurements of lipogenesis in vivo and plasma hormone concentrations in response to starvation and refeeding. 72 15

Women differ markedly from men in their metabolic response to caloric deprivation. To determine if these differences could be attributed solely to changes in insulin concentration, a group of 8 women was matched with a group of 7 men so that the mean fall in serum insulin during a 72-h fast did not differ between the groups. Glucose levels fell to a greater degree in the women than in the men. The serum concentrations of free fatty acids and ketone bodies rose more rapidly in the women and closely paralleled the earlier rise in glucagon concentrations. Over the first 36 h of fasting the change in free fatty acids was positively correlated to the change in glucagon and negatively correlated to the change in insulin. For the second 36 h of fasting, only changes in glucagon correlated with changes in free fatty acids. These correlations were true for both sexes and support the hypothesis that glucagon plays a physiologically significant role the regulation of lipolysis during starvation.
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PMID:Sex variations in free fatty acids and ketones during fasting: evidence for a role of glucagon. 75 30

Oral glucose tolerance tests were performed on 14 lean and 14 obese nondiabetic subjects before and after a 6-day fast. In addition, insulin tolerance tests were performed on 8 lean and 8 obese subjects before and after starvation. Both in lean and obese subjects glucose tolerance deteriorated during starvation, but much more so in the lean population. During fasting, insulin elevation after a glucose load was significantly delayed in lean subjects but not in the obese. Circulating levels of factors known to affect glucose tolerance, such as glucagon, growth hormone, free fatty acids, and ketone bodies were higher in fasting lean than in fasting obese individuals. In normals fasting resulted in a significant decrease of the blood glucose response to insulin injection, whereas in fasting obese subjects glucose response was unchanged. The results obtained suggest that the effect of fasting on insulin release and insulin sensitivity was more pronounced in lean than in obese subjects, which resulted in greater deterioration of glucose tolerance in the lean population.
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PMID:Mechanism of glucose intolerance during fasting: differences between lean and obese subjects. 89 29

The high blood cholesterol and glucagon levels of suckling rats can be rapidly decreased within 24 hours by prematurely weaning rats to a high carbohydrate diet on day 18. The fall in the cholesterol level is much smaller if rats are starved for 24 hours. This decrease can partly be inhibited by injections of glucagon. The only factor so far found to decrease blood cholesterol levels in suckling rats was starvation. Insulin, which slightly but significantly, depressed the level in 40 day old rats, increased it in suckling ones, as does prednisolone. It is concluded that blood cholesterol levels are more easily manipulated in suckling rats than in older rats, and that this is probably related to a different hormonal balance.
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PMID:Control of blood cholesterol levels in suckling and weanling rats. 90 64

Glucagon binding by liver cell membranes was examined in rats with chronically elevated plasma levels of immunoreactive glucagon (IRG) resulting from insulin deficiency, starvation, or twice daily glucagon injections. The concentration of specific glucagon binding sites was significantly reduced in the three chronically hyperglucagonemic (IRG greater than 125 pg/ml) groups as compared with nondiabetic controls and insulin-treated diabetic control rats with only mild hyperglucagonemia. A reduction in glucagon binding sites did not occur with hyperglucagonemia of 12 h or less. Despite the reduced binding of glucagon in the three chronically hyperglucagonemic groups, the ability of glucagon to stimulate cAMP production was not reduced. It is concluded that while decreased glucagon binding occures in the forms of chronic hyperglucagonemia studied, it is not associated with a reduction in the ability of glucagon to stimulate cAMP production.
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PMID:Binding and biologic activity of glucagon in liver cell membranes of chronically hyperglucagonemic rats. 91 19


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